الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
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Abstract
The present results revealed that the stock of Serranid species in the Egyptian Red Sea appears to be overexploited since the current fishing mortality is higher than F0.1 and Fmax. Thus a fishing mortality reduction is necessary in order to avoid future loss in stock productivity and landings. So, it recommended that:
Fishing effort must be controlled and decreased. The available assessment suggests a target reference point at E0.5. So, not less than 40% decreasing in fishing effort should applied to Serranid species in the Red Sea fishing ground to maintain their spawning biomass.
Defining nursery areas of important species should be taken into consideration for recommending closed areas.
Improving the fisheries data recording system, and catch- effort data collection.
Improving fishing pattern of the artisanal fisheries to safe the small and young fishes.
Education and creation of awareness among fishers on the negative impact of fishing and marketing of small size individuals.
Revision of fisheries laws and applies strict punishment towards illegal fishers.
SUMMARY
The Red Sea is one of the important seas over the world; due to its paradise view contains highly biodiversity of all categories (corals, benthos, fishes, etc…….). Fishes and corals play important role in the tourism and fisheries of great economic importance. These need continuous monitoring and management from all stakeholders particularly the scientists.
Hurghada and Shalateen fishing grounds are famous Egyptian fishing areas on the Egyptian Red Sea. They are important sources of local and economic fishes in Red Sea, and play an essential role in the fish production in Egypt. The family Serranidae is economically valuable fish in the Red Sea for both tourism and fisheries sectors. So, these species were studied her in different scientific fields like biology and dynamics to estimate the basic parameters needed for the improvement of grouper fish’ fishery status in Hurghada and Shalateen fishing areas. The outputs of this study were summarized as followings:
Fisheries Statistics
• The main types of fishing of Hurghada and Shalateen area are artisanal fishing (gill and trammel net and long line).
• The vessels length of the gill and trammel net ranged from 5 to 17 m (woody) with motor from 25 to 80 hp, its fishing season from September to May and trip duration from 7 to 10 days.
• The study focused on two grouper species in Hurghada and Shalateen fishing areas; Epinephelus summana (Forsskål, 1775) and Cephalopholis argus (Schneider, 1801).
Otolith morphometrics
• This work highlights the role of otolithic morphometrics and shape indices in the identification of the studied grouper species from the Red Sea.
• The greatest otolith area ranging from 22.75 to 68.36 mm for both left and right otolith for E. summana.
• The otoliths of C. argus was smaller than E. summana, where the mean value of left and right otolith length were 10.84±1.61 and
10.82±1.65 for E. summana, and 8.23±0.91and 8.20±0.90 for C. argus.
• The overall otolith measurements of E. summana was largest than C. argus in all otolith measurements.
Age and growth
Standard Length-Weight relationship
• The mean weight of each length class of two grouper species considered. The length weight relationship for each species under
study is expressed by the following equations:
E. summana W= 0.0218SL3.057 R2= 0.98
C. argus W= 0.0232SL3.0382 R2= 0.93
• The growth in weight relative to fish size in E. summana and C. argus was isometric.
• Based on the number of annuli on the otoliths, the age was composed of tenth (1-10 yr) and six (1-6 yr) age groups for E. summana and C. argus, respectively. It is found that the age group two was the most dominant age group forming 46.09 % and 22.33
% of the total collected samples for E. summana and C. argus,
respectively.
• The estimated von Bertalanffy growth equations in both length and weight were as follows:
E. summana
For growth in length Lt = 63.39 [1 - e -0.13 (t + 1.70)]
For growth in weight Wt = 7034.42 [1- e -013 (t + 1.70)] 3.057
C. argus
For growth in length Lt = 44.22 [1 - e -0.26 (t + 1.33)]
For growth in weight Wt = 2318.87 [1 - e -0.26 (t + 1.33)] 3.0382
• The computed growth performance index (Ø’) for the grouper fish
species under investigation were 2.73 and 2.71 for respectively.
Population dynamics
• The length, at which 50% of the fish become sexually mature, was estimated at 28 and 22.3 cm for E. summana and C. argus respectively.
• Corresponding to an age of 2.62 and 1.36 year respectively. It is evident that a considerable proportion of grouper fish catch didn’t reach the first sexual maturity and sampled fish were smaller than
15 cm total length.
• The total length ranged between 17 to 51 cm for E. summana and
18 to 38 cm, C. argus. The length at first capture were 18.18 and
18.34 cm for E. summana and C. argus, respectively, which corresponding 0.81 and 0.72 year, respectively.
• The estimated values of the total mortality coefficient (Z) were
0.82/year and 1.31/year ages for E. summana and C. argus,
respectively.
• The natural mortality coefficient (M) was estimated as the geometric mean of three methods and the obtained values of (M) were 0.33/ year and 0.56/ year for E. summana and C. argus, respectively.
• The estimated values of fishing mortality coefficient (F) were estimated as F = 0.49/ year, and 0.74/ year for two species respectively.
• The annual mortality rates were estimated to be 0.56 year-1 and
0.73 year-1 for E. summana and C. argus, respectively. While the survival rate (S) was calculated as 0.60 and 0.57 year-1 respectively. The present level of exploitation E = 0.60/year and E= 0.57/year for E. summana and C. argus, respectively. They are higher than the calculated E0.5 (E0.5 = 0.36 for E. summana and
0.38 for C. argus) which is needed to maintain 50% of the stock biomass.
Management
• For management purposes, the relative yield per recruit
(exploitation rate) of E. summana should be reduced from 0.60 to
0.30 (36%) and should be reduced from 0.57 to 34 (38 %) for C. argus, in addition, for to maintain a sufficient spawning biomass.
• By this information, the present study gave some target reference points for sustainable development of grouper fish stock in Hurghada and Shalateen fishing area